The vote was a nonbinding straw poll and has no bearing on the selection of the state’s 43 delegates. Of those, 40 are up for grabs, but they will not be picked until later.

All four candidates remaining in the race -- Mr. Romney, Rick Santorum, Representative Ron Paul and Newt Gingrich -- actively campaigned in Washington, but none concentrated their efforts there as intensely as Mr. Paul.

Mr. Romney and Mr. Santorum, the leading rivals for the nomination, had hoped for some momentum from Washington heading into the big vote next week on Super Tuesday, when 10 states vote.

“The voters of Washington have sent a signal that they do not want a Washington insider in the White House,” Mr. Romney said in a statement as he campaigned in Ohio. All three of his opponents are tied to the nation’s capital, but he has focused his attacks on Mr. Santorum as an insider who does not understand the economy.

Romney's share of Washington's delegates remains to be seen, but does this latest win -- his fourth in a row -- suggest that good things are ahead for often-embattled front-runner on Super Tuesday?